package com.yangzheandroid.rxmvp.utils;

import java.io.File;
import java.io.FileInputStream;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * 采贝科技有限公司  版权所有(c)
 * Author：yangjilai
 * Time: 2016/8/22 19:28
 * <p/>
 * 功能描述:
 */
public class MD5Utils {
    /**
     * 获取一个文件的Md5值
     *
     * @param file
     * @return
     */
    public static String getFileMD5(File file) {
        if (!file.isFile()) {
            return null;
        }
        MessageDigest digest = null;
        FileInputStream in = null;
        byte buffer[] = new byte[1024];
        int len;
        try {
            digest = MessageDigest.getInstance("MD5");
            in = new FileInputStream(file);
            while ((len = in.read(buffer, 0, 1024)) != -1) {
                digest.update(buffer, 0, len);
            }
            in.close();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        return bytesToHexString(digest.digest());
    }

    public static String bytesToHexString(byte[] src) {
        StringBuilder stringBuilder = new StringBuilder("");
        if (src == null || src.length <= 0) {
            return null;
        }
        for (int i = 0; i < src.length; i++) {
            int v = src[i] & 0xFF;
            String hv = Integer.toHexString(v);
            if (hv.length() < 2) {
                stringBuilder.append(0);
            }
            stringBuilder.append(hv);
        }
        return stringBuilder.toString();
    }


    /**
     * 对字符进行md5加密
     */
    public static String md5(String plainText) {
        byte[] secretBytes = null;
        try {
            secretBytes = MessageDigest.getInstance("md5").digest(
                    plainText.getBytes());
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("没有md5这个算法！");
        }
        String md5code = new BigInteger(1, secretBytes).toString(16);
        int len = md5code.length();
        for (int i = 0; i < 32 - len; i++) {
            md5code = "0" + md5code;
        }
        return md5code;
    }
}

